Method of manufacturing basic lead sulphate



DeC- 31, 1935 F. E. GREGORY ET AL METHOD OF MANUFACTURING BASIC LEAD SULPHATE Filed March 50, 1935 UNITED STATES PATENT oFElcE METHOD F MANUFACTURING BASIC LEAD SULPHATE I Fred E. Greg Galena,

Ory, Ruby, Ariz., Kans., and Paul R.

John I. McClaren, Hamilton, Joplin,

Mo., assignors to The Eagle-Picher Lead Company, Cincinnati,

Ohio, a corporation of Ohio Application March 30, 1933, Serial No. 663,546

The object of our inventio 1 Claims.

n is to produce basic sulphate blue lead pigment under controlled conditions, to meet specications of the trade today, or any specifications which may be set up in the future.

Another object of our invention is to produce basic sulphate blue lead pigment with uniform chemical content and color, by means of controlled conditions.

Basic sulphate blue lead is a fume product derived from lead sulphide ores, or the sulphated secondary products resulting from the smelting of lead sulphide ores, by a process of sublimation in special furnaces.

The standard specifications of the trade today are as follows:

Carbon and undertermined matter not over 5 Heretofore certain diiiiculties have been met with in all previous processes for the production of this pigment, by reason of the unstable methof manufacture which rendered uncertain the production of a pigment with both suitable chemical content and color.

To provide a remedy for these defects and bring basic sulphate blue lead to standard chemical specifications and standard color specifications,

we cause to combine in a common flue the fumes from an ore hearth, smelting lead bearing materials or lead by-products, and the fumes from a special furnace, called treating lead bearing a ash roasting furnace, material or lead by-products. In operating the ash roasting furnace lead bearing materials or lead by-products are introduced through a nozzle by means of compressed air into a heated furnace.

This results in the sublimation of the lead bearing materials or lead by-products. By means of f eed and temperature use lead sulphide ore,

control we produce from this furnace a fume of the desired color and chemical content which, when intermingled in the settling system with the fume from the ore hearth, produces a homogeneous product of the desired quality. 5

In the drawing,

Figure 1 represents an ore hearth from which the lead fumes escape 'in a settling system 2. The large particles of burned lead sulphide fall into the hopper 3, the balance of the material being 1Q transported by the air blast from the furnace and fans along the settling system 2, the heavier material being caught in a second hopper 4, While the lighter material enters the bag house.

The burned lead sulphide from hopper 3, and hopper 4 are removed and ground in the ball mill and are passed by any suitable means into a feed bin 6, and then through a small nozzle 'l by means of compressed air (not shown) into the furnace 8. The escaping fumes pass into the flue 9 and from there into the settling system 2, Where they are intimately admixed with fumes from the ore hearth. The combined fumes after passing through the settling system pass into the bag house, and after cooling are packed in barrels for shipment.

Instead of using burned lead sulphide We may or a mixture of lead sulphide ore and burned lead sulphide. Having thus disclosed our invention We claim: The step by step. process of manufacturing basic sulphate blue lead comprising the steps of introducing fumes from an ore hearth into a settling system; removing burned lead sulphide particles from the settling system; grinding the burned lead sulphide particles; introducing the ground particles into a flash furnace; causing the into the settling system and intimately mixing the same with the fumes from the ore hearth.

F. E. GREGORY.

J. I. MCCLAREN.

PAUL R. HAMILTON. 

